[benchmark] migrate to fsdp/ddp after jit, from fsdp/ddp before jit

[crcrpar]

Llama-2-7b-hf & fsdp

container of 20240804. 8 H100 80GB HBM3. command: torchrun --nproc_per_node=8 thunder/benchmarks/benchmark_litgpt.py --compile=thunder_inductor_cat --model_name=Llama-2-7b-hf --distributed_mode=fsdp --shard_mode=zero2 --bucketing_mode=none

	main 5cc3011	pr 3869547
token/s	85765.16	85695.95
tokens/s/GPU	10720.65	10711.99
Memory	42.06 GB	42.06 GB

cc @mpatel31415

related:

• https://github.com/Lightning-AI/lightning-thunder/issues/478